Resource Constrained Project Scheduling Problem Research Articles

A moving block sequence-based evolutionary algorithm for resource-constrained project scheduling problems

In this paper, a new representation for resource-constrained project scheduling problems (RCPSPs), namely moving block sequence (MBS), is proposed. In RCPSPs, every activity has fixed duration and resource demands, therefore, it can be modelled as a rectangle block whose height represents the resource demand and width the duration. Naturally, a project that consists of N activities can be represented as the permutation of N blocks that satisfy the precedence constraints among activities. To decode an MBS to a valid schedule, four move modes are designed according to the situations that how every block can be moved from its initial position to an appropriate location that can minimise the makespan of the project. Based on MBS, the multiagent evolutionary algorithm (MAEA) is used to solve RCPSPs. The proposed algorithm is labelled as MBSMAEA-RCPSP, and by comparing with several state-of-the-art algorithms on benchmark J30, J60, J90 and J120, the effectiveness of MBSMAEA-RCPSP is clearly illustrated.

Combinatorial versus Priority Based Optimization in Resource Constrained Project Scheduling Problems by Nature Inspired Metaheuristics

This paper explores the behavior of the Flower Pollination Algorithm (FPA) and Particle Swarm Optimization (PSO) metaheuristic algorithm in resolving Resource Constrained Project Sched ...

A new approach for the multi-site resource-constrained project scheduling problem

In recent years, the study of Resource Constrained Project Scheduling Problem RCPSP which as a well-known NP-hard problem in project management and operational research is taking substantial interest. The present work investigates a new RCPSP extension in multi-site environments with resource pooling between different sites. This extension considers two types of resources: fixed and mobile resources. New constraints are taken into account like transfer times of mobile resources and the decision on which site a task is carried out. We propose a new Particle Swarm Optimization-based solution to deal with this RCPSP variant aiming at minimizing the total project Makespan. The proposed algorithm uses a Valid Particle Generator to produce feasible schedules. As well, inertia weight is adaptively tuned to realize a trade-off between diversification and intensification. Our solution has been tested on a set of newly created benchmarks to reveal very promising results.

On some implementations of solving the resource constrained project scheduling problems

We consider a resource-constrained project scheduling problem with respect to the makespan minimization criterion. The problem accounts for technological constraints of activities precedence together with resource constraints. Activities pre- emptions are not allowed. The problem with renewable resources is NP-hard in the strong sense. We propose an exact branch and bound algorithm for solving the problem with renewable resources. It uses our new branching scheme based on the representation of a schedule in form of the activity list. We use two approaches of constructing the lower bound. We present results of numerical experiments, illustrating the quality of the proposed lower bounds. The test instances are taken from the library of test instances PSPLIB.

“A Based-Bee Algorithm Approach for the Multi-Mode Project Scheduling Problem”

Solving the resource constrained project scheduling problem (RCPSP) through exact and approximate approaches has an important role in real life to the extent that they support making decisions regards to the allocation of resources and activities scheduling. Accordingly, this work presents a Based-Bee algorithm for the RCPSP under multi-mode conditions in order to minimize the total completion time of the project. The complexity of this problem lies mainly in the various modes in which activities can be performed; each mode has variations on the activity duration and resources requirements. The algorithm uses random keys strategies to guarantee feasible solutions are always reached. The proposed approach is evaluated with benchmark instances from PSLIB and compared with the recent competitive algorithms reported in literature.

An Interval Programming Based Approach for fully uncertain Resource-Constrained Project Scheduling Problem Considering Project Manager’s Attitude toward Risk

An Interval Programming Based Approach for fully uncertain Resource-Constrained Project Scheduling Problem Considering Project Manager’s Attitude toward Risk

Zero-One Formulation for a Partial Resource-Constrained Project Scheduling Problem with Generalized Precedence Relations

AbstractThe resource-constrained project scheduling problem (RCPSP) aims to arrange activities to meet resource restrictions. In real life, not all resource types are constrained, nor do all activi...

Competence-based estimation of activity duration in IT projects

The aim of project management is to successfully complete the project on schedule and within budget. Estimation of project activity duration is a key feature of scheduling. The individual activities making up the schedule and the estimation of their duration are crucial for defining the project timetable. The resulting scheduling problem falls into the class of Multi-Skill Resource-Constrained Project Scheduling Problems. In this paper we propose a novel methodology for Activity Duration Estimation in IT projects. The methodology uses the Hierarchical Skill Model and takes into account the experience of project team members, described by required and possessed skills. Skills are modeled as a weighted digraph, and learning curves are used to express individual learning rates. An illustrative example using a software project is provided. Incorporating skill-based modeling into project scheduling results in more precise estimation of actual and future performance.

An efficient pseudo-polynomial algorithm for finding a lower bound on the makespan for the Resource Constrained Project Scheduling Problem

Several algorithms for finding a lower bound on the makespan for the Resource Constrained Project Scheduling Problem (RCPSP) were proposed in the literature. However, fast computable lower bounds usually do not provide the best estimations and the methods that obtain better bounds are mainly based on the cooperation between linear and constraint programming and therefore are time-consuming. In this paper, a new pseudo-polynomial algorithm is proposed to find a makespan lower bound for RCPSP with time-dependent resource capacities. Its idea is based on a consecutive evaluation of pairs of resources and their cumulated workload. Using the proposed algorithm, several bounds for the PSPLIB benchmark were improved. The results for industrial applications are also presented where the algorithm could provide good bounds even for very large problem instances.

A novel algorithm for solving resource-constrained project scheduling problems: a case study

PurposeConstruction projects managers try their best for the project to go according to the plans. They always attempt to complete the projects on time and consistent with the predetermined budgets. Amid so many problems in project planning, the most critical and well-known problem is the Resource-Constrained Project Scheduling Problem (RCPSP). The purpose of this paper is to solve RCPSP using hybrid algorithm ICA/PSO.Design/methodology/approachDue to the existence of various forms for scheduling the problem and also the diversity of constraints and objective functions, myriad of research studies have been conducted in this realm of study. Since most of these problems are NP-hard ones, heuristic and meta-heuristic methods are used for solving these problems. In this research, a novel hybrid method which is composed of meta-heuristic methods of particle swarm optimization (PSO) and imperialist competitive algorithm (ICA) has been used to solve RCPSP. Finally, a railway project has been examined for RCPS Problem in a real-world situation.FindingsAccording to the results of the case study, ICA/PSO algorithm has better results than ICAs and PSO individually.Practical implicationsICA/PSO algorithm could be used for solving problems in a multi-mode situation of activities or considering more constraints on the resources, such as the existence of non-renewable resources and renewable. Based on the case study in construction project, ICA/PSO algorithm has a better solution than PSO and ICA.Originality/valueIn this study, by combining PSO and ICA algorithms and creating a new hybrid algorithm, better solutions have been achieved in RCPSP. In order to validate the method, standard problems available in PSPLib library were used.

Integration of routing into a resource-constrained project scheduling problem

The resource-constrained project scheduling problem (RCPSP), one of the most challenging combinatorial optimization scheduling problems, has been the focus of a great deal of research, resulting in numerous publications in the last decade. Previous publications focused on the RCPSP, including several extensions with different objectives to be minimized and constraints to be checked. The present work investigates the integration of the routing, i.e., the transport of the resources between activities into the RCPSP, and provides a new resolution scheme. The two subproblems are solved using an integrated approach that draws on both a disjunctive graph model and an explicit modeling of the routing. The resolution scheme takes advantage of an indirect representation of the solution to define both the schedule of activities and the routing of vehicles. The routing solution is modeled by a set of trips that define the loaded transport operations of vehicles that are induced by the flow in the graph. The numerical experiments prove that the models and the methods introduced in this paper are promising for solving the RCPSP with routing.

Evolving heuristics for the resource constrained project scheduling problem with dynamic resource disruptions

Abstract Dynamic changes and disruptions are encountered frequently in the domain of project scheduling. The nature of these dynamic events often requires project managers to make quick decisions with regards to effectively re-scheduling the activities. Priority heuristics have a significant potential for such applications due to their simplicity, intuitiveness and low computational cost. In this research, we focus on automated evolution of priority heuristics using a genetic programming hyper-heuristic (GPHH). The proposed approach uses a multi-objective scheme (MO-GPHH) to evolve priority heuristics that can perform better than the existing rules, and at the same time have low complexity. Furthermore, unlike the existing works on evolving priority heuristics that focus on only static problems, this study covers both static and dynamic instances. The proposed approach is tested on a practical dynamic variant of the classical resource constrained project scheduling problem (RCPSP) in which the resource availability varies with time and knowledge about these changes and disruptions only become available as the project progresses. Extensive numerical experiments and benchmarking are performed to demonstrate the efficacy of the proposed approach.

A novel branch-and-bound algorithm for the chance-constrained resource-constrained project scheduling problem

The resource-constrained project scheduling problem (RCPSP) has been widely studied during the last few decades. In real-world projects, however, not all information is known in advance and uncertainty is an inevitable part of these projects. The chance-constrained resource-constrained project scheduling problem (CC-RCPSP) has been recently introduced to deal with uncertainty in the RCPSP. In this paper, we propose a branch-and-bound (B&B) algorithm and a mixed integer linear programming (MILP) formulation that solve a sample average approximation of the CC-RCPSP. We introduce two different branching schemes and eight different priority rules for the proposed B&B algorithm. The computational results suggest that the proposed B&B procedure clearly outperforms both a proposed MILP formulation and a branch-and-cut algorithm from the literature.

Solving a new multi-objective resource constrained project scheduling problem by SAICA and compare it with DE method

Nowadays the Resource Constrained Project Scheduling Problem (RCPSP) has triggered a substantially significant issue among scheduling problems. The purpose of RCPSP is minimizing the duration of the projects due to both limited available resources and precedence constraints. Indeed, it attempts to consume the total resources by finding the best duration for each activity. This paper proposes a new multi-objective mathematical model for multi-mode RCPSP with interruption to minimize the completion time of the project, maximize the Net Present Value (NPV) of the project, and minimize the allocating workforce’s costs to perform required skills of all activities. To solve the proposed model, an efficient method based on Me measure is used to cope with the uncertainties, and TH method is utilized to convert the multi-objective method into the single one. Furthermore, this paper presents a novel hybrid meta-heuristic algorithm based on Imperialist Competitive Algorithms (ICA) named Self-Adaptive Imperialist Competitive Algorithm (SAICA) to solve the mathematical model which has never been used to solve this type of problems before. Also, to evaluate the proposed method, its performance is investigated against some meta-heuristic algorithms: Differential Evolution (DE) and Imperialist Competitive Algorithm (ICA). Then, a numerical example, two case studies and a real case study have been carried out to embody both validity and efficiency of the presented approach. The obtained results embody that the proposed SAICA is more effective and practical in comparison with DE, ICA, and BCO in decreasing the project duration and also, the considerable effect on solutions confirms the quality of the proposed method.

An S-graph Based Approach for Multi-Mode Resource-Constrained Project Scheduling with Time-Varying Resource Capacities

The Resource-Constrained Project Scheduling Problem (RCPSP) is a general problem class of scheduling problems. It even contains the well-known job shop scheduling problem as a special case. In these problems, jobs demand different amounts from multiple resources at once. The goal is to minimize completion time while satisfying resource capacity constraints throughout the schedule. The RCPSP has several variations and generalizations, one of which is the multi-mode problem. Multiple operation modes are given for jobs, differing in resource usages and execution times. Another generalization is where resources have time-varying capacities instead of a constant limit. The S-graph framework was developed for batch process scheduling and used successfully in various applications. The advantages of this approach motivate research to extend its capabilities to more general problem classes and apply it in various specialized case studies. The authors have previously presented an extension of the S-graph framework for RCPSP and its multi-mode generalization. In this work, a further extension is proposed for handling time-varying capacities. The method relies on a model transformation technique and recent algorithmic developments of the framework.

Estimation of Distribution Algorithm for solving the Multi-mode Resource Constrained Project Scheduling Problem

The Multi-mode Resource Constrained Project Scheduling Problem is characterized by a set of tasks, resources and an objective function. All tasks of a project must be organized carefully taking into account precedence relations, the mode in which they are performed and availability of resources at a

Profit-oriented scheduling of resource-constrained projects with flexible capacity constraints

We consider a novel generalization of the resource-constrained project scheduling problem (RCPSP). Unlike many established approaches for the RCPSP that aim to minimize the makespan of the project for given static capacity constraints, we consider the important real-life aspect that capacity constraints can often be systematically modified by temporarily assigning costly additional production resources or using overtime. We, furthermore, assume that the revenue of the project decreases as its makespan increases and try to find a schedule with a profit-maximizing makespan. Like the RCPSP, the problem is mathcal {NP}-hard, but unlike the RCPSP, it turns out that an optimal schedule does not have to be among the set of so-called active schedules. Scheduling such a project is a formidable task, both from a practical and a theoretical perspective. We develop, describe, and evaluate alternative solution encodings and schedule decoding mechanisms to solve this problem within a genetic algorithm framework and we compare the solutions obtained to both optimal reference values and the results of a commercial local search solver called LocalSolver.

Improved discrete cuckoo search for the resource-constrained project scheduling problem

An Improved Discrete Cuckoo Search (IDCS) is proposed in this paper to solve resource-constrained project scheduling problems (RCPSPs). The original Cuckoo Search (CS) was inspired by the breeding behaviour of some cuckoo species and was designed specifically for application in continuous optimisation problems, in which the algorithm had been demonstrated to be effective. The proposed IDCS aims to improve the original CS for solving discrete scheduling problems by reinterpreting its key elements: solution representation scheme, Lévy flight and solution improvement operators. An event list solution representation scheme has been used to present projects and a novel event movement and an event recombination operator has been developed to ensure better quality of received results and improve the efficiency of the algorithm. Numerical results have demonstrated that the proposed IDCS can achieve a competitive level of performance compared to other state-of-the-art metaheuristics in solving a set of benchmark instances from a well-known PSPLIB library, especially in solving complex benchmark instances.

Resource-Constrained Scheduling for Maritime Traffic Management

We address the problem of mitigating congestion and preventing hotspots in busy water areas such as Singapore Straits and port waters. Increasing maritime traffic coupled with narrow waterways makes vessel schedule coordination for just-in-time arrival critical for navigational safety. Our contributions are: 1) We formulate the maritime traffic management problem based on the real case study of Singapore waters; 2) We model the problem as a variant of the resource-constrained project scheduling problem (RCPSP), and formulate mixed-integer and constraint programming (MIP/CP) formulations; 3) To improve the scalability, we develop a combinatorial Benders (CB) approach that is significantly more effective than standard MIP and CP formulations. We also develop symmetry breaking constraints and optimality cuts that further enhance the CB approach's effectiveness; 4) We develop a realistic maritime traffic simulator using electronic navigation charts of Singapore Straits. Our scheduling approach on synthetic problems and a real 55-day AIS dataset results in significant reduction of the traffic density while incurring minimal delays.

Evolving priority rules for resource constrained project scheduling problem with genetic programming

The main task of scheduling is the allocation of limited resources to activities over time periods to optimize one or several criteria. The scheduling algorithms are devised mainly by the experts in the appropriate fields and evaluated over synthetic benchmarks or real-life problem instances. Since many variants of the same scheduling problem may appear in practice, and there are many scheduling algorithms to choose from, the task of designing or selecting an appropriate scheduling algorithm is far from trivial. Recently, hyper-heuristic approaches have been proven useful in many scheduling domains, where machine learning is applied to develop a customized scheduling method. This paper is concerned with the resource constrained project scheduling problem (RCPSP) and the development of scheduling heuristics based on Genetic programming (GP). The results show that this approach is a viable option when there is a need for a customized scheduling method in a dynamic environment, allowing the automated development of a suitable scheduling heuristic.